The current proposal is an application for a Career Development Award in aging research (K08). The applicant is a new researcher with training in medicine and nutritional epidemiology. The applicant's research will focus on the nutritional determinants of low lung function. Lung function deteriorates gradually with increasing age and lung function decline is accelerated in older adults. Low lung function is an independent predictor of mortality among the elderly. The major clinical manifestation of low lung function, chronic obstructive pulmonary disease (COPD), is the fourth leading cause of death in the United States. COPD prevalence and mortality are increasing, but few preventive strategies are available other than avoidance of smoking. Diet may play an important role in the prevention of accelerated lung function decline and COPD. The current proposal will serve as a bridge to an independent investigator career in the nutritional and genetic epidemiology of respiratory disease and aging. The career development/training activities include mentored advancement in the design and implementation of epidemiological studies, and conferences/lab training/course work on aging, lung function, genetics and statistical modeling in genetics, and grantsmanship. The research proposal will include: 1) primary data collection to validate the Multi-Ethnic Study of Atherosclerosis (MESA) food frequency questionniare (FFQ) items;and 2) investigation of associations of two dietary factors (a pro-oxidant and an anti-oxidant) and related biochemical markers and gene variants with lung function and lung density in the MESA and the Cardiovascular Health Study (CHS)/AII-Stars Study. This proposal will be testing the following hypotheses: A) the MESA FFQ is valid in estimating intake of nitrite/nitrate and cured meats;B) high intake of nitrite/nitrate and cured meats and elevated plasma levels of 3-nitrotyrosine (3-NT) are associated with lower lung function, lower lung density, and greater longitudinal decline in lung density in MESA;C) high intake of vitamin D and dairy products and elevated levels of 25(OH) vitamin D are associated with higher lung function, higher lung density, and slower longitudinal decline in lung density in MESA;D) high cured meat intake is associated with greater longitudinal decline in lung function, and high dairy intake is associated with slower longitudinal decline in lung function in CHS;and E) variants of genes involved in the nitric oxide (or nitrite) production pathway (iNOS, IMF-alpha, IL-1beta, IFN-gamma, VEGF, and NF-kappaB) and encoding vitamin D-binding protein are associated with lung function and lung density and longitudinal change in lung density in MESA. The research plan has the potential to elucidate the role of a novel dietary oxidant and antioxidant in the prevention of age-related decline in lung function and COPD. This proposal will prepare the candidate well to apply successfully for R01 on diet, diet-related genes, and gene-diet interactions in lung function and COPD.